I think that if you missed out on the sunrise period and the landrush - you missed out on probably the biggest domain name release since .com.
.co, over time, will blow the doors off of any of the soon-to-be released gTld's, and in time will be arguably more important than .net and .org.
Google has already stated they'll treat it as a generic Tld, even though it is a ccTld.
.co already gets lots of .com typo traffic, right out of the gate - probably more than .cm.
It is short, very similar to .com, which most people know and love. Many ccTld's also contain .co - like .co.uk, etc....
It is fairly cheap, has a reputable registrar, and in a stable country - Colombia.
Lots of great keywords available, still - despite the fact that it is the most successful new Tld launch ever.
With all this said - it is not an overnight success and will take time for consumers and end-users to build up brand-recognition and trust in it.
My verdict is that you should still be trying to get .com domains for your current and long-term projects to build your empire on, but start buying a few .co's here and there for some of your current projects and save some back for the future - and start doing some aggressive testing and full-on development on .co domains now.
GS